Start by describing what the variables in that equation represent. E.g. "If a torque (variable name) acts on a mass with ..."logan said:ET=iα
Ok, so can you calculate the angular acceleration?logan said:Torque = Inertia x angular acceleration
No, you can calculate the angular acceleration from the information given.logan said:to get angular acceleration you would have to do angular acceleration=Torque/Inertia and we don't know the torque
logan said:0 to 1500 rpm in 4.6 s
Units?logan said:so a=w/t
1500/4.6=326.08
does rpm divided by seconds give rad/s2?logan said:rad/s2
You have to convert from rpm to units involving radians, but not merely radians. Radians per ...?logan said:so you have to convert the 1500 to rads?
Eh?logan said:157/4.6=34013 rad
Ok. What about this part:logan said:radians per second
?logan said:157/4.6=34013 rad
You have 157 rad/s, and you are dividing by 4.6 s. What units result?logan said:so 157/4.6=34 radians per second?
Rad/s2, yes.logan said:Is it rad/s squared
No, as you wrote the equation is τ=Iα, where τ is torque, I is moment of inertia and α is angular acceleration.logan said:I=ta
Go back and read the last sentence of post #20. How did I say you were to find the moment of inertia?logan said:I=t/a
so t is 4.6 but how do you get the torque to solve for inertia
thanks for helping me out so much I am just so lost with this again thank you
That is the information you have about the disc itself, i.e. as an object. From that you can calculate its moment of inertia. Have you not been taught any equations for that?logan said:the disk is 250 g and 25-cm-diameter
Then see http://hyperphysics.phy-astr.gsu.edu/hbase/tdisc.htmllogan said:no my professor only went over Torque = Inertia x angular acceleration because he thinks by making the homework hard the test will be easy for us
Try to keep everything in SI units. You converted cm to m ok, but you also need to convert the g to kg.logan said:so Ix would be .976
1/4(250)(.125)squared
I get 6.67x10-2.CWatters said:Just for info I made it 6.45x10-2Nm
To calculate the torque, you will need to know the rotational inertia of the disk, the angular velocity, and the time it takes to reach that velocity. The formula for torque is torque = rotational inertia x angular acceleration. You can find the rotational inertia by multiplying the mass of the disk by the square of its radius. The angular velocity can be calculated by dividing the total angle turned by the time it takes to turn that angle.
The rotational inertia, also known as moment of inertia, depends on the shape and distribution of mass of the object. For a disk, the formula for rotational inertia is 1/2 x mass x radius^2. Therefore, for a 250g plastic disk, the rotational inertia will be 1/2 x 0.25kg x (radius)^2.
The angular velocity can be calculated by dividing the total angle turned by the time it takes to turn that angle. For example, if the disk spins 180 degrees in 4.6 seconds, the angular velocity would be 180 degrees/4.6 seconds, or approximately 39.13 degrees per second.
Yes, you can use any unit of mass as long as it is consistent throughout the calculation. For example, if you use kilograms for the mass of the disk, you will need to use kilograms for the rotational inertia as well.
The torque is directly proportional to the angular acceleration of the disk. This means that the greater the torque, the faster the disk will spin. However, other factors such as friction and air resistance may also affect the spinning of the disk.